Any feedback?
Please rate this page
(literature.php)
(0/150)

BRENDA support

Literature summary for 3.2.1.B28 extracted from

  • Petzelbauer, I.; Reiter, A.; Splechtna, B.; Kosma, P.; Nidetzky, B.
    Transgalactosylation by thermostable beta-glycosidases from Pyrococcus furiosus and Sulfolobus solfataricus. Binding interactions of nucleophiles with the galactosylated enzyme intermediate make major contributions to the formation of new beta-glycosides (2000), Eur. J. Biochem., 267, 5055-5066.
    View publication on PubMed

KM Value [mM]

KM Value [mM] KM Value Maximum [mM] Substrate Comment Organism Structure
5.3
-
2-nitrophenyl beta-D-galactoside release of 2-nitrophenol, pH 7.5, 80°C Pyrococcus furiosus
186
-
lactose release of D-glucose, pH 7.5, 80°C Pyrococcus furiosus
861
-
methyl beta-D-galactoside release of methanol, pH 7.5, 80°C Pyrococcus furiosus

Organism

Organism UniProt Comment Textmining
Pyrococcus furiosus Q51723
-
-

Substrates and Products (Substrate)

Substrates Comment Substrates Organism Products Comment (Products) Rev. Reac.
2-nitrophenyl beta-D-galactoside
-
Pyrococcus furiosus 2-nitrophenol + D-galactose
-
r
lactose + H2O
-
Pyrococcus furiosus D-glucose + D-galactose
-
r
methyl beta-D-galactoside
-
Pyrococcus furiosus methanol + D-galactose
-
r
additional information enzyme additionally catalyzes transglycosylation reactions, making new beta(1->3) and beta(1->6) glycosidic bonds by intermolecular as well as intramolecular transfer reactions. The intramolecular galactosyl transfer of CelB yields beta-D-Galp-(1->6)-D-glucose and beta-D-Galp-(1->3)-D-glucose in a molar ratio of about 1 : 2. Galactosyl transfer from CelB to D-glucose occurs with partitioning ratios, kNu /kwater, which are 170 times those for the reactions of the galactosylated enzyme with 2-propanol. Therefore, the binding interactions with nucleophiles contribute chiefly to formation of new beta-glycosides during lactose conversion. Likewise, noncovalent interactions with the glucose leaving group govern the catalytic efficiencies for the hydrolysis of lactose Pyrococcus furiosus ?
-
?

Turnover Number [1/s]

Turnover Number Minimum [1/s] Turnover Number Maximum [1/s] Substrate Comment Organism Structure
8.3
-
methyl beta-D-galactoside release of methanol, pH 7.5, 80°C Pyrococcus furiosus
3800
-
lactose release of D-glucose, pH 7.5, 80°C Pyrococcus furiosus
10000
-
2-nitrophenyl beta-D-galactoside release of 2-nitrophenol, pH 7.5, 80°C Pyrococcus furiosus

kcat/KM [mM/s]

kcat/KM Value [1/mMs-1] kcat/KM Value Maximum [1/mMs-1] Substrate Comment Organism Structure
0.01
-
methyl beta-D-galactoside release of methanol, pH 7.5, 80°C Pyrococcus furiosus
20.4
-
lactose release of D-glucose, pH 7.5, 80°C Pyrococcus furiosus
1900
-
2-nitrophenyl beta-D-galactoside release of 2-nitrophenol, pH 7.5, 80°C Pyrococcus furiosus